Saint seija: Omega

Warriors known as "Saints" are champions of hope who have always appeared since the Age of Myth whenever evil threatens the world. They would clad themselves in armor called Myth Cloths, and fight to protect Athena, the goddess who rules the world's surface. Seiya, the Pegasus Saint, has saved Athena many times, and while he and his friends are Bronze Saints, which is the lowest rank, their battles have been passed down as legend. The god of war and guardian of his namesake planet, Mars, was once sealed away by one of those Saints, Seiya. Time has passed and his revival is at hand. Meanwhile, Saori Kida (Athena) is raising Koga, a boy whose life Seiya saved, and he's been training every day to become a Saint in order to prepare for the upcoming crisis... Unaware of his destiny, when Koga awakens to the power of his cosmo hidden inside him, the curtain will rise upon the legend of a new Saint! (Prime Video)